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by bntr 107 days ago
For comparison: factorial(3) visualized in two different notations.

John Tromp's Lambda Diagrams (via 2swap): https://www.youtube.com/watch?v=RcVA8Nj6HEo&t=1346s

Bubble Notation: https://www.youtube.com/watch?v=aRgu8S3Pnb8

2 comments

Here's another from a long time ago: https://dkeenan.com/Lambda/
I like this catalog: https://github.com/prathyvsh/lambda-calculus-visualizations

And it seems that John Tromp's diagrams originate from David C. Keenan's Mockingbird (1996),

and Bubble Notation comes from Wayne Citrin's Visual Expressions (1995)

Thanks for the link! Some very pretty stuff there.

Missing AFAICT are categorical string diagrams. I'm only sort-of familiar with the notation for Haskell Arrows [1,2] but a quick google for "lambda calculus string diagrams" turns up some recent work by Dan Ghica and others that may be of interest.

[1] https://en.wikipedia.org/wiki/String_diagram

[2] Ross Paterson "A New Notation for Arrows" (2001)

Thanks! I liked the pics here: https://piedeleu.com/posts/diagrammatic-lambda-calculus/

I'd love to see them smoothly animated.

2swap has some incredible videos